The castle of Loarre, located in Huesca (Spain), is the best Romanesque fortress in Europe. One of the oldest in Spain. It was built in the most dangerous moments of the reconquest, in the eleventh century, when the Christian kingdoms would have passed to the south of the peninsula. Sancho III, king of Navarre, ordered to build it as advance guard on the Hole of Huesca. The castle was extended by the King of Aragón and Navarra Sancho Ramírez.